Antenna device and electronic device

Abstract

An antenna device includes: a ground upper layer substrate of a dielectric substrate forming a first ground part and a second ground part disposed at a predetermined distance from the first ground part; a ground lower layer substrate of a dielectric substrate forming a third ground part and a fourth ground part disposed at a predetermined distance from the third ground part; and an inner layer substrate of a dielectric substrate forming a fifth ground part. The ground upper layer substrate, inner layer substrate, and lower layer substrate are laminated. The first ground part and third ground part are electrically connected. The second ground part and fourth ground part are electrically connected. The antenna device further includes: a chip antenna disposed on the ground upper layer substrate, transmitting and receiving electromagnetic waves; and an adjustment component electrically connecting the first ground part and second ground part, and adjusting antenna characteristics.

What is claimed is: 
     
       1. An antenna device comprising:
 a ground upper layer substrate of a dielectric substrate forming a first ground element and a second ground element disposed at a predetermined distance from the first ground element; 
 a ground lower layer substrate of a dielectric substrate forming a third ground element and a fourth ground element disposed at a predetermined distance from the third ground element; 
 an inner layer substrate of a dielectric substrate forming a fifth ground element; 
 a chip antenna disposed on the ground upper layer substrate, transmitting and receiving an electromagnetic wave; and 
 an adjustment component electrically connecting the first ground element and the second ground element, and adjusting an antenna characteristic, 
 wherein the ground upper layer substrate, the inner layer substrate, and the lower layer substrate are laminated in this order, 
 the first ground element and the third ground element are electrically connected by a first conductive via, 
 the second ground element and the fourth ground element are electrically connected by a second conductive via, 
 the first ground element and the second ground element are formed in the same layer and are non-contiguous with one another, and 
 the fifth ground element is not electrically connected to any one of the first ground element, the second ground element, the third ground element, and the fourth ground element. 
 
     
     
       2. The antenna device according to  claim 1 , wherein a length in a longitudinal direction of the first ground element is ¼ of a wavelength of the electromagnetic wave the chip antenna receives. 
     
     
       3. The antenna device according to  claim 1 , wherein a length in a longitudinal direction of the second ground element is between ¼ and 1/16 inclusive of a wavelength of the electromagnetic wave the chip antenna receives. 
     
     
       4. An electronic device comprising:
 the antenna device, according to  claim 1 , transmitting and receiving a wireless signal; and 
 a wireless communications circuit applying predetermined signal processing to the wireless signal. 
 
     
     
       5. The antenna device of  claim 1 , wherein the third ground element and the fourth ground element are formed in the same layer and are non-contiguous with one another. 
     
     
       6. The antenna device of  claim 1 , wherein the predetermined distance between the first ground element and the second ground element is taken along the longitudinal axis of the ground upper layer substrate. 
     
     
       7. The antenna device of  claim 1 , wherein the predetermined distance between the third ground element and the fourth ground element is taken along the longitudinal axis of the ground lower layer substrate. 
     
     
       8. The antenna device of  claim 1 , wherein the first conductive via and the second conductive via are separated by a material having a composition which is different from the composition of a material forming the first conductive via and the second conductive via. 
     
     
       9. The antenna device of  claim 1 , wherein the chip antenna, the first ground element, the adjustment component, and the second ground component are disposed in this order along a longitudinal axis of the ground upper layer substrate. 
     
     
       10. The antenna device of  claim 1 , wherein the adjustment component comprises at least one of a coil, a capacitor, a resistor and a bead.